These are record shots, of the Thayer's gull which we were lucky enough to observe today, at RSPB Minsmere. We arrived on site in the afternoon, whilst the identity of the bird was still being discussed as possible Vega gull (Larus vagae) query Thayer's gull, by the local gull experts.
Lacking both the vocabulary and wider experience of tricky gulls, I contributed nothing to this debate, but was more than happy to stay around to hear the identity finally confirmed as Thayer's gull. In doing so we also received a masterclass in the identification of imm. Caspian gull (Larus cacchinans) - so watch this space, as I try to find my own along Southsea sea front!
For a full description of the finding of the bird:
http://www.rarebirdalert.co.uk/v2/Content/Finders_in_the_Field_Thayers_Gull_Minsmere.aspx?s_id=304565937&applefix=true